It is known that, in order to interchangeably bundle sheets, use can be made of binding elements of the type consisting of a back and a number of teeth cooperating therewith. By pulling the teeth open, sheets which are provided with the necessary perforations, can be slid over the teeth, be removed therefrom respectively.
A disadvantage of such binding elements exists in that the bundles bound therewith cannot be placed nicely next to each other, and in that the teeth of the binding elements of bundles which are placed next to each other clench together.
Binding devices in which this disadvantage is excluded to a certain degree are known from the documents FR 834.090, FR 834.827, U.S. Pat. No. 4,711,469 and U.S. Pat. No. 2,112,389. However, the devices described herein present several disadvantages.
The devices described in FR 834.090 and FR 834.827 use open binding rings and are not suitable to apply binding elements with ring-shaped, for instance circular, closed binding rings.
The device described in U.S. Pat. No. 4,711,469 uses a binding file which consists of two separate parts. Applying such a binding file is complicated and removing sheets from or placing sheets in such file, without removing one of said parts, is nearly impossible.
U.S. Pat. No. 2,112,389 provides in a solution for a book, in other words a permanently bound whole, but does not offer a solution for a binding file allowing loose sheets to be bundled interchangeably.